Continuity mistake: When Wolverine crashes into the tree knocked over by Sabertooth, notice that the entire front of the truck gets completely folded up and the windshield breaks into a thousand pieces. In the next frame, Wolverine gets thrown through the unbroken windshield and the front of the truck is practically undamaged...

Continuity mistake: When young Magneto is struggling with the guards at the concentration camp, the father's star switches from one side of his chest to the other.

Revealing mistake: After Toad spits his slime at Jean Grey he falls to the floor. You can see the tether that was holding him in mid air.

Revealing mistake: Right after the scene where Sabretooth dispatches the Liberty Island guard, the camera switches to a head on shot of Magneto's boat ferrying the torch. As the camera moves upward, you can distinctly see the head of someone crouching down next to Mystique as she captains the boat and it is actually the guard that was the boat pilot.

Revealing mistake: Just before Sabretooth grabs Storm at the train station he swats a guy aside who was standing in line behind Storm. You can clearly see a wire attached to the guy to yank him off-frame.

Revealing mistake: The metal bar wrapped around Storm's neck in the Statue of Liberty is noticeably wrinkled. Obviously a painted strip of foam rubber.

Continuity mistake: When Magneto discovers Senator Kelly has got out of his barred window, he then leaves the room, out of an opening he made in the barred door. As he leaves, between three shots the amount of bars that are bent on either side of the opening actually differs.

Continuity mistake: When Mystique reveals herself to Senator Kelly on the helicopter, her blue body is appearing and it shows Senator Kelly watching for a few seconds, but when it shows Mystique again, the blue body thing continues from the part it left off at. It should have been to her legs at the rate it was going at before.

Continuity mistake: Right after Wolverine slices the tip off one of the Statue of Liberty's prongs, he strikes a dramatic pose: left arm cocked at his chest, right arm extended. In the next shot, his right arm is at his shoulder and his left is in front.

Factual error: The helicopter markings and paint schemes are exclusive ONLY to POTUS (President of the United States). Senator Kelly, even thought he's trying to get a Presidential bid, wouldn't be allowed to fly around in aircraft marked like that.

Continuity mistake: After the guy comes at Wolverine with a knife, Wolverine holds him against a wooden post. His jacket is off his shoulders after being pushed against the post, but when Wolverine slices the shotgun in half the jacket is back on his shoulders.

Continuity mistake: When Rogue is seen for the first time, her hand is moving up photographs on the wall, and if you look closely there are some kind of red poppies when she reaches the end, yet when it cuts to another shot a bit further away, her finger is a lot further down the wall from the red poppy/flower.

Continuity mistake: At the start when Rogue walks into the bar, when she walks towards the cage, note all the things around her from the camera's perspective (which is from behind her): the wooden plank in front of her which she walks around, and the burning can to the left of the screen. When the camera cuts to the front, the wooden plank is not there and neither is the burning can (now to the right of the screen).

Continuity mistake: In the Statue of Liberty scene just after Wolverine, Storm Cyclops and Jean go through the metal detectors, they walk off and watch in the background, you can see Wolverine walk past Cyclops yet in the following shot he is walking past again.

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During the last half hour of the movie, when the four X-Men are leaving in the jet, Logan says, "You actually go outside in these things?" to which Cyclops replies, "Well, what would you prefer, yellow spandex?" In the comics, Logan's outfit is yellow spandex.